Add15Minute

using System;

namespace TimePlusFiftheenMin
{
    class Program
    {
        static void Main(string[] args)
        {
            int hour = int.Parse(Console.ReadLine())*60;
            int min = int.Parse(Console.ReadLine())+15;
            var all = hour + min;
            var inHours = all / 60;
            var inMin = all % 60;
            if (inHours>23)
            {
                inHours = 0;
            }
            if (inMin<10)
            {
                Console.WriteLine(inHours + ":0" + inMin);
            }
            else
            {
                Console.WriteLine(inHours + ":" + inMin);
            }
        }
    }
}